Emails disappearing from your inbox can be caused by various reasons. However, one of the most common issues is using different protocols (POP / IMAP) when setting up the email account on multiple devices. To explain in more detail:

IMAP → Works by synchronizing emails with the server.
POP3 → Downloads emails from the server and often deletes them from the server.

For example, if you set up your email as IMAP on your computer but as POP3 on your phone, the emails may be deleted from the server after being downloaded to the phone, which means they will no longer appear on your computer.

In such a case, if you want your emails to stay synchronized across all devices, the most commonly recommended solution is to back up the emails from the device using POP3 and then reconfigure the account using IMAP.

If all devices are using IMAP and emails still seem to be disappearing, you may also want to review the following points below.

  • Your emails might have been delivered to the spam or junk folder. This can make it seem like the emails have disappeared. It’s helpful to check all your mail folders.
  • If you have set up custom filters, your emails might have been redirected to different folders or even to other addresses. Try reviewing your filter and forwarding settings.
  • You may have accidentally deleted the email. In that case, check your trash or deleted items folder.
  • The antivirus software on your device might be detecting an email as a threat and interfering with its delivery.
  • There might be unauthorized access to your email account. We recommend changing your password and enhancing your account security settings.

Additional Information:
If you choose to continue using POP3, after backing up your emails, you can try enabling the “Leave a copy on the server” option from the advanced settings of the email application. This allows the original emails to remain on the server for a specified period before being deleted. However, the general recommendation is to use the same protocol (IMAP) on all devices for better synchronization.